According to Izmir's governor, the blast was caused by an overhead crane that collapsed into a large industrial furnace used during the liquid steel casting process.
Delegates, meeting in the Turkish Mediterranean resort city of Antalya, will come under pressure to develop new pledges for climate action while implementing previous promises.
Grainy CCTV footage published by Turkish media showed a man in a black jacket, white trousers and glasses clutching a rifle as he stood by a faded red minivan.
Ocalan has been imprisoned in a penitentiary on the island of Imrali in the Marmara Sea — which links the Black Sea to the Aegean Sea — since he was captured in 1999.